Process for improving color of polycondensates

ABSTRACT

The present invention relates to a process of preparing a polycondensate in the presence of a fluorescent whitening agent and at least one phosphonate, and/or phosphinate. Further aspects of the invention are a polyester prepared according to this process and composition comprising a polycondensate, a fluorescent whitening agent and at least one phosphonate and/or phosphinate. Yet another aspect is the use of a fluorescent whitening agent and at least one phosphonate and/or phosphinate for improving the color of a polycondensate.

The present invention relates to a process for the preparation ormodification of a polycondensate in the presence of a fluorescentwhitening agent and at least one phosphonate and/or phosphinate. Furtheraspects of the invention are a polyester prepared according to thisprocess and a composition comprising a polycondensate, a fluorescentwhitening agent and at least one phosphonate and/or phosphinate. Yetanother aspect is the use of a fluorescent whitening agent and at leastone phosphonate and/or phosphinate for improving the color of apolycondensate.

Polycondensates, for example polyamides, polycarbonates or polyesters,in particular polyethylene terephthalate (PET) and polybutyleneterephthalate (PBT) as well as polyester copolymers and polyester blendse.g. with polycarbonate (PBT/PC), are important thermo-plasticsbelonging to the group of the engineering plastics. Partiallycrystalline polyesters are used for injection moulding compounds and aredistinguished by high strength and rigidity, high dimensional stabilityand favourable wear characteristics. Amorphous polyesters have hightransparency, superior toughness and excellent stress crackingresistance and are processed, for example, to hollow articles. Anotherfield of application of PET is the production of fibres and foils.

For some applications, such as, for example, packages for beverages andtechnical fibres, higher molecular weights are necessary. These can beobtained by solid phase polycondensation (S. Fakirov, Kunststoffe, 74(1984), 218 and R. E. Grützner, A. Koine, Kunststoffe, 82 (1992), 284).The prepolymer is in this case subjected to thermal treatment above theglass transition temperature and below the melt temperature of thepolymer under inert gas or under vacuum. However, this method is verytime- and energy-consuming. Increasing the intrinsic viscosity requiresa residence time of up to 12 hours under vacuum or under inert gas attemperatures from 180 to 240° C.

Within the context of the present invention the term “polycondensationreaction” means both, the melt polycondensabon of monomers or oligomers,as well as the solid state polycondensation.

Often these articles need very good appearance, particularly in terms ofcolor, clarity and brightness. It is known in the art, that adding aphosphonate during the polycondensation reaction can prevent yellowingof polycondensates. This is, however, in some cases accompanied by adecrease of clarity or brightness.

On the other hand the addition of a fluorescent whitening agent can alsoimprove color and brightness of the polycondensate. This is, forexample, described by A. Wieber in Fluorescent Whitening Agents, editedby R. Anliker and G. Müller, Georg Thieme, 1975 pages 65-82. However,the addition of a fluorescent whitening agent to a polycondensate duringthe condensation reaction imposes great demands on their chemical andthermal behavior. Thermal stability must be high and the compound mustbe inert under the condensation reaction conditions. Moreover, thefluorescent whitening agents need to be stable also during processing ofpolycondensates, which is mainly performed at high temperatures (e.g.above 240° C.). Sometimes recrystallization during cooling of the meltis observed, leading to an undesired discoloration, mainly to a greenishshade.

Another problem is the color contribution of the neat fluorescentwhitening agents. Due to their conjugated aromatic structures, often thefluorescent whitening agents show a yellowish appearance. This colorcontributes to the color of the polycondensate and leads to moreyellowish end products. It is known in the art, that it is difficult tocompensate this effect, while simultaneously improving brightness of thepolycondensates.

Surprisingly, it has been found that polycondensates prepared in thepresence of a fluorescent whitening agent and a phosphonate orphosphinate show excellent brightness and color, in particular noundesired color change, such as a greenish shade or yellowing isobserved.

This is of particular interest in the high demanding applications ofpolycondensates, where appearance and color is essential, such as innon-colored or colored textiles, in packaging applications, in windowsand window films, etc.

To improve color is also advantageous In the case of used or thermallyor hydrolytically damaged polycondensates, where the damage typicallygoes hand in hand with a discoloration.

By means of the process of this invention it is possible to improvecolor of polycondensate recyclates from useful material collections,such as used packages (foils and bottles) and waste textiles. Recyclatescan then be used for high-quality recycling, for example in the form ofhigh-performance fibres, injection moulding articles, in extrusionapplications or in the form of foams. Such recyclates originate, forexample, also from industrial or domestic useful material collections,from production wastes, such as from fibre production and trimmings, orfrom obligatory returnables, such as bottle collections of PET drinkspacks.

One aspect of the invention is a process for the preparation of apolycondensate in a condensation reaction of monomers or oligomers orthe modification of a polycondensate by melt processing or solid-statepolycondensation of the polycondensate, comprising adding during thepolycondensation reaction

-   a1) a compound of formula (I)-   R₁₀₃ is H, C₁-C₂₀alkyl, unsubstituted or C₁-C₄alkyl-substituted    phenyl or naphthyl,-   R₁₀₄ is hydrogen, C₁-C₂₀alkyl, unsubstituted or    C₁-C₄alkyl-substituted phenyl or naphthyl; or-   M^(r+)/r,-   M^(r+) is an r-valent metal cation or the ammonium ion,-   n is 0, 1, 2, 3, 4, 5 or 6, and-   r is 1, 2, 3 or 4;-   Q is hydrogen, —X—C(O)—OR₁₀₇, or a radical-   R₁₀₁ is isopropyl, tert-butyl, cyclohexyl, or cyclohexyl which is    substituted by 1-3 C₁-C₄alkyl groups,-   R₁₀₂ is hydrogen, C₁-C₄alkyl, cyclohexyl, or cyclohexyl which is    substituted by 1-3 C₁-C₄alkyl groups,-   R₁₀₅ is H, C₁-C₁₈alkyl, OH, halogen or C₃-C₇cycloalkyl;-   R₁₀₆ is H, methyl, trimethylsilyl, benzyl, phenyl, sulfonyl or    C₁-C₁₈alkyl;-   R₁₀₇ is H, C₁-C₁₀alkyl or C₃-C₇cycloalkyl; and-   X is phenylene, C₁-C₄alkyl group-substituted phenylene or    cyclohexylene; or-   a2) a compound of formula (II)    -   wherein    -   R₂₀₁ is hydrogen, C₁-C₂₀alkyl, phenyl or C₁-C₄alkyl substituted        phenyl; biphenyl, naphthyl, —CH₂—O—C₁-C₂₀alkyl or        —CH₂—S—C₁-C₂₀alkyl,    -   R₂₀₂ is C₁-C₂₀alkyl, phenyl or C₁-C₄alkyl substituted phenyl;        biphenyl, naphthyl, —CH₂—O—C₁-C₂₀alkyl or —CH₂—S—C₁-C₂₀alkyl, or        R₁ and R₂ together are a radical of the formula III    -   wherein    -   R₂₀₃, R₂₀₄ and R₂₀₅ independently of each other are C₁-C₂₀alkyl,        phenyl or C₁-C₄alkyl substituted phenyl;    -   R₂₀₆ is hydrogen, C₁-C₁₈alkyl or the ion of an alkali metal or        the ammonium ion or    -   R₂₀₆ is a direct bond, which forms together with R₂₀₂ an        aliphatic or aromatic cyclic ester; or-   a3) a compound of formula (I) and formula (II); and-   b) a fluorescent whitening agent selected from the group consisting    of a compound according to formulae 1-8 or a mixture thereof    in which formulae-   R₃ is an unsubstituted or substituted alkyl or aryl group;-   R₄ is M, or an unsubstituted or substituted alkyl or aryl group;-   R₅ is hydrogen; an unsubstituted or substituted alkyl or aryl group;    or —NR₇R₈, wherein R₇ and R₈ are each independently of the other    hydrogen or an unsubstituted or substituted alkyl or aryl group, or    R₇ and R₈ together with the nitrogen atom linking them form a    heterocyclic radical, especially a morpholino or piperidino radical;-   R₆ is hydrogen, or an unsubstituted or substituted alkyl or aryl    group;-   R₂ is hydrogen; an unsubstituted or substituted alkyl or aryl group;    or a radical of formula    —NH₂, —N(CH₂CH₂OH)₂, —N[CH₂CH(OH)CH₃]₂, —NH—R₄, —N(R₄)₂ or —OR₄; or-   R₁ and R₂ are each independently of the other —OH, —Cl, —NH₂,    —O—C₁-C₄alkyl, —O-aryl, —NH—C₁-C₄alkyl, —N(C₁-C₄alkyl)₂,    —N(C₁-C₄alkyl)(C₁-C₄hydroxyalkyl), —N(C₁-C₄hydroxyalkyl)₂, —NH-aryl,    morpholino or —S—C₁-C₄alkyl(aryl);-   R₉ and R₁₀ are each independently of the other hydrogen, C₁-C₄alkyl,    phenyl or a radical of-   R₁₁ is hydrogen, —Cl or SO₃M;-   R₁₂ is —CN, —SO₃M, —S(C₁-C₄alkyl)₂ or —S(aryl)₂;-   R₁₃ is hydrogen, —SO₃M, —O—C₁-C₄alkyl, —CN, —Cl, —COO—C₁-C₄alkyl or    —CON(C₁-C₄alkyl)₂;-   R₁₄ is hydrogen, —C₁-C₄alkyl, —Cl or —SO₃M;-   R₁₅ and R₁₆ are each independently of the other hydrogen,    C₁-C₄alkyl, —SO₃M, —Cl or —O—C₁-C₄alkyl;-   R₁₇ is hydrogen or C₁-C₄alkyl;-   R₁₈ is hydrogen, C₁-C₄alkyl, —CN, —Cl, —COO—C₁-C₄alkyl,    —CON(C₁-C₄alkyl)₂, aryl or —O-aryl;-   M is hydrogen, sodium, potassium, calcium, magnesium, ammonium,    mono-, di-, tri- or tetra-C₁-C₄alkylammonium, mono-, di- or    tri-C₁-C₄hydroxyalkylammonium, or ammonium di- or tri-substituted by    a mixture of C₁-C₄alkyl and C₁-C₄hydroxyalkyl groups; and-   n₁, n₂ and n₃ are each independently of the others 0 or 1.

Preferably no Al containing condensation catalyst is present or has beenused in the polycondensation reaction.

In addition to polyester, polyamide or polycarbonate, this inventionalso embraces the corresponding copolymers and blends, for examplePBT/PS, PBT/ASA, PBT/ABS, PBT/PC, PET/ABS, PET/PC, PBT/PET/PC, PBT/PET,PAIPP, PA/PE and PA/ABS. However, it needs to be taken into account thatthe novel process, like all methods allowing exchange reactions betweenthe components of the blend, may influence the blends, i.e. may resultin the formation of copolymeric structures.

A preferred process is that wherein the polycondensate is an aliphaticor aromatic polyester, an aliphatic or aromatic polyamide orpolycarbonate, or a blend or copolymer thereof.

The polycondensate is for example polyethylene terephthalate (PET),polybutylene therephthalate (PBT), polyethylenenaphthalate (PEN),polytrimethylene terephthalate (PTT), a copolyester, PA 6, PA 6.6, apolycarbonate containing bisphenol A, bisphenol Z or bisphenol F linkedvia carbonate groups.

Preferred polycondensates are PBT, PET or a copolymer with PBT or PET.

The polycondensate may also be a recyclate.

In a specific embodiment of the invention the polycondensate accordingto the above process exhibits a L value, which is greater than 80 and ab value which is less than 2, as measured with a spectrometer accordingto ASTM D1925.

Polyamides, i.e. both virgin polyamides and polyamide recyclates, areunderstood to be, for example, aliphatic and aromatic polyamides orcopolyamides which are derived from diamines and dicarboxylic acidsand/or of aminocarboxylic acid or the corresponding lactams. Suitablepolyamides are for example: PA 6, PA 11, PA 12, PA 46, PA 66, PA 69, PA610, PA 612, PA 10.12, PA 12.12 and also amorphous polyamides andthermoplastic polyamide elastomers such as polyether amides of theVestamid, Grilamid ELY60, Pebax, Nyim and Grilon ELX type. Polyamides ofthe cited type are commonly known and are commercially available.

The polyamides used are preferably crystalline or partially crystallinepolyamides and, in particular, PA6 and PA6.6 or their blends, as well asrecyclates on this basis, or copolymers thereof.

The polyesters, i.e. virgin polyester as well as polyester recyclate,may be homopolyesters or copolyesters which are composed of aliphatic,cycloaliphatic or aromatic dicarboxylic acids and diols orhydroxycarboxylic acids.

The polyesters can be prepared by direct esterification (PTA process)and also by transesterification (DMT process). Any of the known catalystsystems may be used for the preparation.

The components a1), a2), a3) and b) can be added at any stage of thecondensation reaction in either process. Preferably they are presentfrom the beginning. In case that high molecular weights are desired,after melt polycondensation the polycondensate can be subjected to asolid state polycondensation.

Alternatively, the components a1), a2), a3) and b) can be added duringmelt processing. Subsequently, the polycondensate can be subjected to asolid state polycondensation. The components a1), a2), a3) and b) can beadded all at once, or in different process steps, e.g. either componenta1), a2), a3) and b) during melt polycondensation, or component a1),a2), a3 during melt polycondensation and component b) during meltprocessing, or vice versa.

The aliphatic dicarboxylic acids can contain 2 to 40 carbon atoms, thecycloaliphatic dicarboxylic acids 6 to 10 carbon atoms, the aromaticdicarboxylic acids 8 to 14 carbon atoms, the aliphatic hydroxycarboxylicacids 2 to 12 carbon atoms and the aromatic and cycloaliphatichydroxycarboxylic acids 7 to 14 carbon atoms.

The aliphatic diols can contain 2 to 12 carbon atoms, the cycloaliphaticdiol 5 to 8 carbon atoms and the aromatic diols 6 to 16 carbon atoms.

Polyoxyalkylene glycols having molecular weights from 150 to 40000 mayalso be used.

Aromatic diols are those in which two hydroxyl groups are bound to oneor to different aromatic hydrocarbon radicals.

Suitable dicarboxylic acids are linear and branched saturated aliphaticdicarboxylic acids, aromatic dicarboxylic acids and cycloaliphaticdicarboxylic acids. Suitable aliphatic dicarboxylic acids are thosecontaining 2 to 40 carbon atoms, for example oxalic acid, malonic acid,dimethylmalonic acid, succinic acid, pimelic acid, adipic acid,tri-methyladipic acid, sebacic acid, azelaic acid and dimeric acids(dimerisation products of unsaturated aliphatic carboxylic acids such asoleic acid), alkylated malonic and succinic acids such asoctadecylsuccinic acid.

Suitable cycloaliphatic dicarboxylic acids are:1,3-cyclobutanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid,1,3- and 1,4-cyclohexanedicarboxylic acid, 1,3- and1,4-(dicarboxylmethyl)cyclohexane, 4,4′-dicyclohexyldicarboxylic acid.

Suitable aromatic dicarboxylic acids are: In particular terephthalicacid, isophthalic acid, o-phthalic acid, and 1,3-, 1,4-, 2,6- or2,7-naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid,4,4′-diphenylsulfonedicarboxylic acid, 4,4′-benzophenonedicarboxylicacid, 1,1,3-trimethyl-5-carboxyl-3-(p-carboxylphenyl)indane,4,4′-diphenyl ether dicarboxylic acid, bis-p-(carboxylphenyl)methane orbis-p-(carboxylphenyl)ethane.

The aromatic dicarboxylic acids are preferred, in particularterephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylicacid.

Other suitable dicarboxylic acids are those containing —CO—NH-groups;they are described in DE-A2414349. Dicarboxylic acids containingN-heterocyclic rings are also suitable, for example those which arederived from carboxylalkylated, carboxylphenylated or carboxybenzylatedmonoamine-s-triazinedicarboxylic acids (viz. DE-A-2121184 and 2533675),mono- or bishydantoins, optionally halogenated benzimidazoles orparabanic acid. The carboxyalkyl group can in this case contain 3 to 20carbon atoms.

Suitable aliphatic diols are the linear and branched aliphatic glycols,in particular those containing 2 to 12, preferably 2 to 6, carbon atomsin the molecule, for example: ethylene glycol, 1,2- and 1,3-propyleneglycol, 1,2-, 1,3-, 2,3- or 1,4-butanediol, pentyl glycol, neopentylglycol, 1,6-hexanediol, 1,12-dodecanediol. A suitable cycloaliphaticdiol is e.g. 1,4-dihydroxy-cyclohexane. Other suitable aliphatic diolsare e.g. 1,4-bis(hydroxymethyl)cyclohexane, aromatic-aliphatic diolssuch as p-xylylene glycol or 2,5-dichloro-p-xylyiene glycol,2,2-(β-hydroxyethoxyphenyl)propane and also polyoxyalkylene glycols suchas diethylene glycol, triethylene glycol, polyethylene glycol orpolypropylene glycol. The alkylene diols are preferably linear andpreferably contain 2 to 4 carbon atoms.

Preferred diols are the alkylenediols, 1,4-dihydroxycyclohexane and1,4-bis(hydroxymethyl)-cyclohexane. Particularly preferred are ethyleneglycol, 1,4-butanediol and 1,2- and 1,3-propylene glycol.

Other suitable aliphatic diols are the β-hydroxyalkylated, in particularβ-hydroxyethylated, bisphenols such as2,2-bis[4′-(β-hydroxyethoxy)phenyl]propane. Other bisphenols will bementioned later.

Another group of suitable aliphatic diols are the heterocyclic diolsdescribed in DE-A-1812003, DE-A-2342432, DE-A-2342372 and DE-A-2453326,for example: N,N′-bis(β-hydroxyethyl)-5,5-dimethylhydantoin,N,N′-bis(p-hydroxypropyl)-5,5-dimethylhydantoin,methylenebis[N-(β-hydroxyethyl)-5-methyl-5-ethylhydantoin],methylenebis[N-(β-hydroxyethyl)-5,5-dimethylhydantoin],N,N′-bis(β-hydroxyethyl)benzimidazolone,N,N′-bis(β-hydroxyethyl)-(tetrachloro)benzimidazolone orN,N′-bis(β-hydroxyethyl)-(tetrabromo)benzimidazolone.

Suitable aromatic diols are mononuclear diphenols and, in particulardinuclear diphenols carrying a hydroxyl group at each aromatic nucleus.Aromatic will be taken to mean preferably hydrocarbonaromatic radicals,such as phenylene or naphthylene. Besides e.g. hydroquinone, resorcinolor 1,5-, 2,6- and 2,7-dihydroxynaphthalene, the bisphenols are to bementioned in particular, which can be represented by the followingformulae:

The hydroxyl groups can be in m-position, preferably in p-position, andR′ and R″ in these formulae can be alkyl containing 1 to 6 carbon atoms,halogen, such as chloro or bromo, and, in particular, hydrogen atoms. Amay be a direct bond or —O—, —S—, —(O)S(O)—, —C(O)—,—P(O)(C₁-C₂₀alkyl)-, unsubstituted or substituted alkylidene,cycloalkylidene or alkylene.

Examples of unsubstituted or substituted alkylidene are: ethylidene,1,1- or 2,2-propylidene, 2,2-butylidene, 1,1-isobutylidene, pentylidene,hexylidene, heptylidene, octylidene, dichloroethylidene,trichloroethylidene.

Examples of unsubstituted or substituted alkylene are methylene,ethylene, phenylmethylene, diphenylmethylene, methylphenylmethylene.Examples of cycloalkylidene are cyclopentylidene, cyclohexylidene,cycloheptylidene and cyclooctylidene.

Examples of bisphenols are: bis(p-hydroxyphenyl) ether orbis(p-hydroxyphenyl) thioether, bis(p-hydroxyphenyl)sulfone,bis(p-hydroxyphenyl)methane, bis(4-hydroxyphenyl)-2,2′-biphenyl,phenylhydroquinone, 1,2-bis(p-hydroxyphenyl)ethane,1-phenylbis(p-hydroxyphenyl)-ethane,diphenylbis(p-hydroxyphenyl)methane, diphenylbis(p-hydroxyphenyl)ethane,bis(3,5-dimethyl-4-hydroxyphenyl)sulfone,bis(3,5-dimethyl4-hydroxyphenyl)-p-diisopropylbenzene,bis(3,5-dimethyl-4-hydroxyphenyl)-m-diisopropylbenzene2,2-bis(3′,5′-dimethyl-4′-hydroxy-phenyl)propane, 1,1- or2,2-bis(p-hydroxyphenyl)butane,2,2-bis(p-hydroxyphenyl)hexa-fluoropropane, 1,1-dichloro- or1,1,1-trichloro-2,2-bis(p-hydroxyphenyl)ethane,1,1-bis(p-hydroxyphenyl)cyclopentane and, in particular,2,2-bis(p-hydroxyphenyl)propane (bisphenol A) and1,1-bis(p-hydroxyphenyl)cyclohexane (bisphenol C). Suitable polyestersof hydroxycarboxylic acids are, for example, polycaprolactone,polypivalolactone or the polyesters of 4-hydroxycyclohexancarboxylicacid, 2-hydroxy-6naphthalene carboxylic acid or 4-hydroxybenzoic acid.

Other suitable compounds are polymers which may predominantly containester bonds or also other bonds, for example polyester amides orpolyester imides.

Polyesters containing aromatic dicarboxylic acids have become mostimportant, in particular the polyalkylene terephthalates. Accordingly,those novel moulding compositions are preferred wherein the polyesterconsists to at least 30 mol %, preferably to at least 40 mol %, ofaromatic dicarboxylic acids and to at least 30 mol %, preferably to atleast 40 mol %, of alkylenediols containing preferably 2 to 12 carbonatoms, based on the polyester.

In this case the alkylenediol is, in particular, linear and contains 2to 6 carbon atoms, for example ethylene glycol, tri-, tetra- orhexamethylene glycol and the aromatic dicarboxylic acid, terephthalicacid and/or lsophthalic acid.

Particularly suitable polyesters are PET, PBT, PEN, PTT andcorresponding copolymers, PET and its copolymer being especiallypreferred. The process is also particularly important in the case of PETrecyclates originating, for example, from bottle collections such ascollections of the beverages industry. These materials preferablyconsist of terephthalic acid, 2,6-naphthalenedicarboxylic acid and/orisophthalic acid in combination with ethylene glycol, diethylene glycoland/or 1,4-bis(hydroxymethyl)cyclohexane.

Polyester blends to be mentioned in particular are those comprisingpolycarbonate.

Polycarbonate (PC) is understood to mean both virgin polycarbonate andpolycarbonate recyclate. PC is obtained, for example, from bisphenol Aand phosgene or phosgene analog such as trichloromethylchloroformate,triphosgene or diphenylcarbonate, by condensation in the latter caseusually with addition of a suitable transesterification catalyst, forexample a boron hydride, an amine, such as 2-methylimidazole or aquatemary ammonium salt; in addition to bisphenol A other bisphenolcomponents may also be used and it is also possible to use halogenatedmonomers in the benzene nucleus. Particularly suitable bisphenolcomponents to be mentioned are: 2,2-bis(4′-hydroxyphenyl)propane(bisphenol A), 2,4′-dihydroxy-diphenylmethane,bis(2-hydroxyphenyl)methane, bis(4-hydroxyphenyl)methane,bis(4-hydroxy-5-propylphenyl)methane, 1,1-bis(4′-hydroxyphenyl)ethane,bis(4-hydroxyphenyl)-cyclohexylmethane,2,2-bis(4′-hydroxyphenyl)-1-phenylpropane,2,2-bis(3′,5′-dimethyl-4′-hydroxyphenyl)propane,2,2-bis(3′,5′-dibromo-4′-hydroxyphenyl)propane,2,2-bis(3′,5′-dichloro-4′-hydroxyphenyl)propane,1,1-bis(4′-hydroxyphenyl)cyclododecane,1,1-bis(3′,5′-dimethyl-4′-hydroxyphenyl)cyclododecane,1,1-bis(4′-hydroxyphenyl)-3,3,5-trimethylcyclohexane,1,1-bis(4′-hydroxyphenyl)-3,3,5,5-tetramethylcyclohexane,1,1-bis(4′-hydroxyphenyl)-3,3,5-trimethylcyclopentane and the bisphenolsmentioned above. The polycarbonates may also be branched by suitableamounts of more than difunctional monomers (examples as indicated abovefor the polyesters).

The polyester copolymers or blends, which may be used In the novelprocess are prepared in customary manner from the starting polymers. Thepolyester component is preferably PET, PBT, and the PC component ispreferably a PC based on bisphenol A. The ratio of polyester to PC ispreferably from 95:5 to 5:95, a particularly preferred ratio being thatin which one component makes up at least 75%.

It is also possible that the polyesters are branched with small amounts,e.g. from 0.1 to 3 mol %, based on the dicarboxylic acids present, ofmore than difunctional monomers (e.g. pentaerythritol, trimellitic acid,1,3,5-tri(hydroxyphenyl)benzene, 2,4-dihydroxybenzoic acid or2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)propane).

Further examples of difunctional and more than difunctional monomers aregiven below.

A useful polyanhydride is for example a polyanhydride which has 2-8anhydride functions, it being possible for free carboxylic acid groupsor carboxylates to be present besides the anhydride functions.

It is preferred to use tetracarboxylic dianhydrides.

Tetracarboxylic dianhydrides, which may be used within the scope of thisinvention are those

wherein R is C₄-C₂₀alkantetrayl or a radical of formulae (Xa)-(Xj)

wherein Q is —CH₂—, —CH(CH₃)—, —C(CH₃)₂—, —C(CF₃)₂—, —S—, —O—, —SO₂—,—NHCO—, —CO— or >P(O)(C₁-C₂₀alkyl) and wherein the aromatic rings in theformulae (Va)-(Ve) are unsubstituted or substituted by one or severalC₁-C₆alkyl groups, C₁-C₆alkoxy groups or halogen atoms.

If R is an alkanetetrayl radical, then the tetracarboxylic dianhydridemay be, for example, butane-1,2,3,4-tetracarboxylic dianhydride.

Preferred tetracarboxylic dianhydrides are those containing aromaticrings.

Particularly preferred are pyromellitic dianhydride,3,3′,4,4′-benzophenonetetracarboxylic dianhydride,3,3′,4,4′-biphenyltetracarboxylic dianhydride and oxydiphthalicdianhydride.

Where appropriate it is also possible to use a blend of tetracarboxylicdianhydrides of different structure.

Individual particularly preferred tetracarboxylic dianhydrides are:pyromellitic dianhydride, benzophenonetetracarboxylic dianhydride,1,1,2,2-ethanetetracarboxylic dianhydride,1,2,3,4-cyclopentanetetracarboxylic dianhydride,diphenylsulfonetetracarboxylic dianhydride,5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3cyclohexane-1,2-dicarboxylic dianhydride, bis-(3,4-dicarbonacidphenyl)ether dianhydride, bis(3,4-dicarboxylic acid phenyl)thioetherdianhydride, bisphenol A bisether dianhydride, 2,2-bis(3,4-dicarboxylicphenyl)hexafluoropropane dianhydride, 2,3,6,7-naphthalenetetracarboxylicdianhydride, bis(3,4-dicarboxylic acid phenyl)sulfone dianhydride,1,2,5,6-naphthalenetetracarboxylic dianhydride,2,2′,3,3′-biphenyl-tetracarboxylic dianhydride, hydroquinone bisetherdianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride,1,2,3,4-cyclobutanetetracarboxylic dianhydride,3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic dianhydride,bicyclo(2,2)oct-7-ene-2,3,5,6-tetracarboxylic dianhydride,tetrahydrofuran-2,3,4,5-tetracarboxylic dianhydride,2,2-bis(3,4-dicarboxyphenyl)propane dianhydride,3,3′,4,4′-biphenyltetracarboxylic dianhydride, 4,4′-oxydiphthalicdianhydride (ODPA), ethylenediaminetetracarboxylic dianhydride (DDTAH),or a combination of these dianhydrides.

The polyfunctional compound is for example a polyfunctional hydroxylcompound (polyol), a polyfunctional epoxy compound, a polyfunctionalamine compound (polyamine), a polyfunctional aziridine compound(polyaziridine), a polyfunctional isocyanate compound (polyisocyanate),a polyfunctional oxazoline compound (polyoxazoline), a polyfunctionalthioalcohol, or a combination of these compounds.

It is preferred to use a polyol consisting of phenols and/or alcoholscontaining 3-10 free hydroxyl groups, a polythiol consisting ofthiophenols and/or thioalcohols containing 310 free thiol groups, anaromatic and/or aliphatic polyamine containing 3-10 free amino groups, apolyoxazoline, a polyaziridine or an epoxy compound containing at leasttwo epoxy groups.

Polyfunctional, in particular difunctional, compounds from the class ofthe epoxides in the sense of this invention may have an aliphatic,aromatic, cycloaliphatic, araliphatic or heterocyclic structure; theycontain epoxy groups as side groups or these groups form part of analicyclic or heterocyclic ring system. The epoxy groups are preferablybound as glycidyl groups via ether or ester bonds to the remainingmolecule, or they are N-glycidyl derivatives of heterocyclic amines,amides or imides. Epoxides of this type are commonly known and arecommercially available.

The epoxides contain, for example, two epoxy radicals, for example thoseof formula IV

which radicals are directly bound to carbon, oxygen, nitrogen or sulfuratoms, wherein, if R₂₀₅ and R₂₀₇ are hydrogen, R₂₀₆ is hydrogen ormethyl and p=0; or, if R₂₀₅ and R₂₀₇ together are —CH₂—CH₂— or—CH₂—CH₂—CH₂—, R₂₀₆ is hydrogen and p=0 or 1.

Examples of epoxides to be mentioned are:

1. Diglycidyl ester and di(β-methylglycidyl)ester obtainable by reactinga compound containing two carboxyl groups in the molecule withepichlorohydrin or glycerol dichlorohydrin or β-methylepichlorohydrin.The reaction is usefully carried out in the presence of bases.

Compounds containing two carboxyl groups in the molecule may bealiphatic dicarboxylic acids. Examples of these dicarboxylic acids areglutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid,sebadc acid or dimerised or trimerised linolic acid.

However, it is also possible to use cycloaliphatic dicarboxylic acids,such as tetrahydrophthalic acid, 4-methyltetrahydrophthalic acid,hexahydrophthalic acid or 4-methylhexahydrophthalic acid.

Aromatic dicarboxylic acids may also be used, such as phthalic acid orisophthalic acid.

2. Diglycidyl ether or di(β-methylglycidyl)ether obtainable by reactinga compound containing two free alcoholic hydroxyl groups and/or phenolichydroxyl groups with a suitably substituted epichlorohydrin underalkaline conditions or in the presence of an acid catalyst withsubsequent treatment with alkali.

Ethers of this type are derived, for example, from acyclic alcohols,such as ethylene glycol, diethylene glycol and higherpoly(oxyethylene)glycols, propane-1,2-diol, orpoly(oxypropylene)glycols, propane-1,3-diol, butane-1,4-diol,poly(oxytetramethylene)glycols, pentane-1,5-diol, hexane-1,6-diol,sorbitol, and from polyepichlorohydrins.

They are also derived, for example, from cycloaliphatic alcohols such as1,3- or 1,4-dihydroxycyclohexane, bis(4-hydroxycyclohexyl)methane,2,2-bis(4-hydroxycyclohexyl)propane or1,1-bis(hydroxymethyl)-cyclohex-3-ene, or they have aromatic nuclei suchas N,N-bis(2-hydroxyethyl)aniline orp,p′-bis(2-hydroxyethylamino)diphenylmethane.

The epoxides can also be derived from mononuclear phenols, for examplefrom resorcinol, pyrocatechol or hydroquinone; or they are based onpolynuclear phenols such as on 4,4′-dihydroxybiphenyl,bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane,2,2-bis-(3,5-dibromo-4-hydroxyphenyl)propane,4,4′-dihydroxydiphenylsulfone, 9,9′-bis(4-hydroxy-phenyl)fluorene, or oncondensates, obtained under acid conditions, of phenols withformaldehyde such as phenol novolaks.

3. Di(N-glycidyl) compounds are obtainable, for example, bydehydrochlorination of the reaction products of epichlorhydrin withamines containing two aminohydrogen atoms. These amines are, forexample, aniline, toluidine, n-butylamine, bis(4-aminophenyl)methane,m-xylylenediamine or bis(4-methylaminophenyl)methane.

The di(N-glycidyl) compounds also include N,N′-diglycidyl derivatives ofcycloalkylene ureas, such as ethylene urea or 1,3-propylene urea, andN,N′-diglycidyl derivatives of hydantoins, such as of5,5-dimethylhydantoin.

4. Di(S-glycidyl) compounds, such as di-S-glycidyl derivatives, whichare derived from dithiols, such as ethane-1,2-dithiol orbis(4-mercaptomethylphenyl) ether.

5. Epoxides containing a radical of formula IV, wherein R₂₀₅ and R₂₀₇together are —CH₂—CH₂— and n is 0, for example bis(2,3-epoxycyclopentyl)ether, 2,3-epoxycyclopentyl glycidyl ether or1,2-bis(2,3-epoxycyclopentyloxy)ethane; epoxides containing a radical offormula IV, wherein R₅ and R₇ together are —CH₂—CH₂— and n is 1, forexample 3,4-epoxy-6-methylcyclo-hexanecarboxylicacid-(3′,4′-epoxy-6′-methylcyclohexyl)methyl ester.

Due to e.g. the process for their preparation, the difunctional epoxidesmentioned above can contain minor amounts of mono- or trifunctionalcomponents.

Diglycidyl compounds having aromatic structures are mainly used.

Where appropriate, it is also possible to use a blend of epoxides ofdifferent structure. On the other hand it is also possible to use tri-and polyfunctional epoxides as supplement in order to obtain branchings,if desired. Such epoxides are, for example, a) liquid diglycidyl ethersof bisphenol A such as Araldit®GY 240, Araldit®GY 250, Araldit®GY 260,Araldit®GY 266, Araldit®GY 2600, Araldit®MY 790; b) solid diglycidylethers of bisphenol A such as Araldit®GT 6071, Araldit®GT 7071,Araldit®GT 7072, Araldit®GT 6063, Araldit®GT 7203, Araldit®GT 6064,Araldit®GT 7304, Araldit®GT 7004, Araldit®GT 6084, Araldit®GT 1999,Araldit®GT 7077, Araldit®GT 6097, Araldit®GT 7097, Araldit®GT 7008,Araldit®GT 6099, Araldit®GT 6608, Araldit®GT 6609, Araldit®GT 6610; c)liquid diglycidyl ethers of bisphenol F such as Araldit®GY 281,Araldit®GY282, Araldit®PY 302, Araldit®PY 306; d) solid polyglycidylethers of tetraphenylethane such as CG Epoxy resin®0163; e) solid andliquid polyglycidyl ethers of phenolformaldehyde novolak such as EPN1138, EPN 1139, GY 1180, PY 307; f) solid and liquid polyglycidyl ethersof o-cresolformaldehyde novolak such as ECN 1235, ECN 1273, ECN 1280,ECN 1299; g) liquid glycidyl ethers of alcohols such as Shells glycidylether 162, Araldit®DY 0390, Araldit®DY 0391; h) liquid glycidyl estersof carboxylic acids such as Shell®Cardura E terephthalate, trimellitate,Araldit®PY 284 or mixtures of aromatic glycidyl esters such asAraldit®PT 910; i) solid heterocyclic epoxy resins (triglycidylisocyanurate) such as Araldit®PT 810; j) liquid cycloaliphatic epoxyresins such as Araldit®CY 179; k) liquid N,N,O-triglycidyl ethers ofp-aminophenol such as Araldit®MY 0510; l)tetraglycidyl-4-4′-methylenebenzamine orN,N,N′,N′-tetraglycidyldlaminophenylmethane such as Araldit®MY 720,Araldit®MY 721.

Particularly preferred difunctional epoxides are diglycidyl ethers basedon bisphenols, for example based on 2,2-bis(4-hydroxyphenyl)propane(bisphenol A), bis(4-hydroxyphenyl)-sulfone (bisphenol S), mixtures ofbis(ortho/para-hydroxyphenyl)methane (bisphenol F) or Araldit®MT 0163.

Solid epoxides of the diglycidyl ether of bisphenol A type are veryparticularly preferred, e.g.: Araldit® GT 6071, GT 7071, GT 7072, GT6097 and GT 6099 or liquid epoxides of the bisphenol F type such asAraldit® GY 281 or PY 306.

Preferably 0.01-5 parts, more preferably 0.02 to 2 parts; mostpreferably 0.05 to 1 part, of a diepoxide are used, based on 100 partsof polycondensate.

Polyfunctional, in particular trifunctional, compounds from the class ofthe oxazolines in the sense of this invention are known and aredescribed, inter alia, in EP-A-0583807 and are, for example, compoundsof formula V

wherein R₄₀₈, R₄₀₉, R₄₁₀ and R₄₁₁ are each independently of one anotherhydrogen, halogen, C₁-C₂₀alkyl, C₄-C₁₅cycloalkyl, unsubstituted orC₁-C₄alkyl-substituted phenyl; C₁-C₂₀alkoxy or C₂-C₂₀carboxyalkyl,

-   if t=3,-   R₄₁₂ is a trivalent linear, branched or cyclic aliphatic radical    containing 1 to 18 carbon atoms which may be interrupted by oxygen,    sulfur or    or R₁₂ is also an unsubstituted or C₁-C₄alkyl-substituted    benzenetriyl,-   if t=2,-   R₄₁₂ is a divalent linear, branched or cyclic aliphatic radical    containing 1 to 18 carbon atoms which may be interrupted by oxygen,    sulfur or    or R₄₁₂ is also an unsubstituted or C₁-C₄alkyl-substituted    phenylene, R₄₁₃ is C₁-C₈alkyl, and t is 2 or 3.

Halogen is, for example, fluoro, chloro, bromo or iodo. Chloro isparticularly preferred.

Alkyl containing up to 20 carbon atoms is a branched or unbranchedradical, for example methyl, ethyl, propyl, isopropyl, n-butyl,sec-butyl, isobutyl, tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl,1-methylpentyl, 1,3-dimethylbutyl, n-hexyl, 1-methylhexyl, n-heptyl,isoheptyl, 1,1,3,3-tetramethylbutyl, 1-methylheptyl, 3-methylheptyl,n-octyl, 2-ethylhexyl, 1,1,3-trimethylhexyl, 1,1,3,3-tetramethylpentyl,nonyl, decyl, undecyl, 1-methylundecyl, dodecyl,1,1,3,3,5,5-hexamethylhexyl, tridecyl, tetradecyl, pentadecyl,hexadecyl, heptadecyl, octa-decyl, eicosyl or docosyl. A preferredmeaning of R₈, R₉, R₁₀ and R₁₁, is C₁-C₁₂alkyl, in particularC₁-C₈alkyl, e.g. C₁-C₄alkyl.

C₄-C₁₅Cycloalkyl, in particular C₅-C₁₂cycloalkyl, is e.g. cyclobutyl,cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl or cyclododecyl.C₅-C₈Cycloalkyl is preferred, in particular cyclohexyl.

C₁-C₄Alkyl-substituted phenyl which preferably contains 1 to 3, morepreferably 1 or 2, alkyl groups is, for example, o-, m- orp-methylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl,2,5-dimethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl,3,5-dimethylphenyl, 2-methyl-6-ethylphenyl, 4-tert-butylphenyl,2-ethylphenyl or 2,6-diethylphenyl.

Alkoxy containing up to 20 carbon atoms is a branched or unbranchedradical, for example methoxy, ethoxy, propoxy, isopropoxy, n-butoxy,isobutoxy, pentoxy, isopentoxy, hexoxy, heptoxy, octoxy, decyloxy,tetradecyloxy, hexadecyloxy or octadecyloxy. A preferred meaning of R₈,R₉, R₁₀ and R₁₁ is alkoxy containing 1 to 12, preferably 1 to 8, e.g. 1to 4, carbon atoms.

Carboxyalkyl containing 2 up to 20 carbon atoms is a branched orunbranched radical, for example carboxymethyl, carboxyethyl,carboxypropyl, carboxybutyl, carboxypentyl, carboxyhexyl, carboxyheptyl,carboxyoctyl, carboxynonyl, carboxydecyl, carboxyundecyl,carboxydodecyl, 2-carboxy-1-propyl, 2-carboxy-1-butyl or2-carboxy-1-pentyl. A preferred meaning of R₈, R₉, R₁₀ and R₁₁ isC₂-C₁₂carboxyalkyl, in particular C₂-C₈carboxyalkyl, e.g.C₂-C₄carboxyalkyl.

A trivalent linear, branched or cyclic aliphatic radical containing 1 to18 carbon atoms, which radical may be interrupted by oxygen, sulfur or

means that the three bonding sites may be at the same atom or atdifferent atoms. Examples thereof are methanetriyl, 1,1,1-ethanetriyl,1,1,1-propanetriyl, 1,1,1-butanetniyl, 1,1,1-pentanetriyl,1,1,1-hexanetriyl, 1,1,1-heptanetriyl, 1,1,1-octanetriyl,1,1,1-nonanetriyl, 1,1,1-decanetriyl, 1,1,1-undecanetriyl,1,1,1-dodecanetriyl, 1,2,3-propanetriyl, 1,2,3-butanetriyl,1,2,3-pentanetriyl, 1,2,3-hexanetriyl, 1,1,3-cyclopentanetriyl,1,3,5-cyclohexanetriyl, 3-oxo-1,1,5-pentanetriyl,3-thio-1,1,5-pentanetriyl or 3-methylamino-1,1,5-pentanetriyl.

A divalent linear, branched or cyclic aliphatic radical containing 1 to18 carbon atoms, which radical may be interrupted by oxygen, sulfur or

means that the two bonding sites may be at the same atom or at differentatoms. Examples thereof are methylene, ethylene, propylene, butylene,pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecyleneor dodecylene.

Unsubstituted or C₁-C₄alkyl-substituted benzenetriyl which preferablycontains 1 to 3, more preferably 1 or 2, alkyl groups is, for example,1,2,4-benzenetriyl, 1,3,5-benzenetriyl, 3-methyl-1,2,4-benzoltriyl or2-methyl-1,3,5-benzenetriyl. 1,2,4-Benzenetriyl and 1,3,5-benzenetriylare particularly preferred.

Particularly interesting compounds are those of formula V, wherein R₈,R₉, R₁₀ and R₁₁ are each independently of one another hydrogen orC₁-C₄alkyl, and R₁₂ is 1,2,4-benzenetriyl or 1,3,5-benzenetriyl.

Especially interesting are compounds of formula V, such as2,2′,2″-(1,3,5-benzoltriyl)-tris-2-oxazoline;2,2′,2″-(1,2,4-benzoltriyl)-tris-4,4-dimethyl-2-oxazoline;2,2′,2″-(1,3,5-benzoltriyl)-tris-4,4-dimethyl-2-oxazoline;2,2′,2″-(1,2,4-benzoltriyl)-tris-5-methyl-2-oxazoline; or2,2′,2″-(1,3,5-benzoltriyl)-tris-5-methyl-2-oxazoline.

Preferred difunctional compounds from the class of the bisoxazolines inthe sense of this invention are described by T. Loontjens et al.,Makromol. Chem., Macromol. Symp. 75, 211-216 (1993) and are, forexample, compounds of formulae

Polyfunctional, in particular difunctional, compounds from the class ofthe isocyanates in the sense of this invention are known and are, forexample, compounds of formula VIIO═C═N—R₂₃—N═C═O  (VII),wherein R₂₃ is C₁-C₂₀alkylene or polymethylene, arylene, aralkylene orcycloalkylene. Preferred diisocyanates are tetramethylenediisocyanate,hexamethylenediisocyanate, dodecamethylenediisocyanate,eicosan-1,20-diisocyanate, 4-butylhexamethylenediisocyanate, 2,2,4- or2,4,4-trimethylhexamethylenediisocyanate, OCN(CH₂)₂O(CH₂)₂NCO,toluene-2,4-di-isocyanate, p-phenylenediisocyanate,xylylenediisocyanate,3-isocyanatomethyl-3,5,5-tri-methylcyclohexylisocyanate,naphthalenediisocyanate, sulfonyidiusocyanate, 3,3′-, 4,4′- and3,4′-diisocyanates of diphenylmethane, 2,2-diphenylpropane and diphenylether, 3,3′-di-methyl-4,4′-diisocyanatodiphenyl,3,3′-dimethoxy-4,4′-diisocyanatodiphenyl and4,4′-diiso-cyanatodiphenylmethane.

The diisocyanates listed above are commercially available or can beprepared from commercially available amines.

It is also possible to use diisocyanate generators, such as polymericurethanes, uretdion dimers and higher oligomers, cyanurate polymers,urethanes and polymeric urethanes of cyanurate polymers and thermallydissociable adducts of Schiffs bases.

Polyfunctional compounds from the class of the alcohols in the sense ofthis invention are known and are, for example, pentaerythritol,dipentaerythritol, tripentaerythritol, bistrimethylolpropane,bistrimethylolethane, trismethylolpropane, sorbitol, maltite,isomaltite, lactite, lycasine, mannitol, lactose, leucrose,tris(hydroxyethyl)isocyanurate, palatinite, tetramethylol-cyclohexanol,tetramethylolcyclopentanol, tetramethylolcyclopyranol, glycerol,diglycerol, polyglycerol or 1-0-α-D-glycopyranosyl-D-mannitoldihydrate,1,1,1-tris(4-hydroxyphenyl)-ethane,4,6-dimethyl-2,4,6-tris(4-hydroxyphenyl)heptane,2,2-bis(4-(4-hydroxyphenyl)cyclohexyl)propane, 1,3,5trihydroxybenzene,1,2,3-trihydroxybenzene, 1,4-bis(4-hydroxyphenyl) phenyl)benzene,2,3,4-trhydroxyacetophenone, 2,3,4-trihydroxybenzoic acid,2,3,4-trihydroxybenzophenone, 2,4,4′-trihydroxybenzophenone,2′,4′,6′-trihydroxy-3-(4-hydroxyphenyl)propiophenone,pentahydroxyflavone, 3,4,5-trihydroxypyrimidine,3,4,5-trihydroxyphenyl-methylamine, tetrahydroxy-1,4-quinonehydrate,2,2′,4,4′tetrahydroxybenzophenone or 1,2,5,8-tetrahydroxyanthraquinone.Pentaerythritol, dipentaerythritol and tris(hydroxyethyl)-isocyanurateare preferred.

Preferably, the polyol is glycerol or pentaerythritol; the epoxycompound is aminophenol triglycidyl ether, trimellitic acid triglycidylester or Araldit MT 0163; the oxazollne is2,2′-bis-(4H-3,1-benzoxazin-4-one), the polyamine is 2-aminomalonamine,1,2,3-triaminopropane, triaminobenzene, triaminotoluene,triaminoanisole, triaminonaphthalene, triaminopyridine,triaminopyrimidine, tetraaminopyrimidine, tetraaminobenzene,tetraaminodiphenyl, tetraaminodiphenylsulfone, hexaaminodiphenyl,trlamincyclopropane; the polyaziridine istris[1-(2-methyl)aziridinyl]phosphine oxide, and the polythiol is1,2,34rimercaptopropane, trimercaptobenzene or trimercaptoaniline.

This invention is also of interest in the case of polyester recyclates,such as are recovered from production wastes, useful materialcollections or through so-called obligatory returnables e.g. from theautomotive industry or from the electronics area. The polycondensaterecyclates are in this case in many ways thermally and/or hydrolyticallydamaged. These recyclates may additionally also contain subordinateamounts of admixtures of plastics of different structure, for examplepolyolefins, polyurethanes, ABS or PVC. Furthermore, these recyclatesmay also contain admixtures owing to standard impurities, such asresidues of colourants, adhesives, contact media or paints, traces ofmetal, water, operating agents, or inorganic salts.

The phosphonates of formula (I) are known and may be prepared accordingto standard methods, such as for example described in U.S. Pat. No.4,778,840. However there are further suitable phosphonates, which arelisted below.

Sterically hindered hydroxyphenylalkylphosphonic acid esters orhalf-esters, such as those known from U.S. Pat. No. 4,778,840, areparticularly preferred.

Examples for the substituents of the compounds of formula (I) are givenbelow.

Halogen is fluoro, chloro, bromo or iodo.

Alkyl substituents containing up to 18 carbon atoms are suitablyradicals such as methyl, ethyl, propyl, butyl, pentyl, hexyl and octyl,stearyl and also corresponding branched isomers; C₂-C₄alkyl and isooctylare preferred.

C₁-C₄Alkyl-substituted phenyl or naphthyl which preferably contain 1 to3, more preferably 1 or 2, alkyl groups is e.g. o-, m- orp-methylphenyl, 2,3-dimethylphenyl, 2,4-dimethylphenyl,2,5-imethylphenyl, 2,6-dimethylphenyl, 3,4-dimethylphenyl,3,5-dimethylphenyl, 2-methyl-6-ethylphenyl, 4-tert-butylphenyl,2-ethylphenyl, 2,6-diethylphenyl, 1-methyinaphthyl, 2-methyl-naphthyl,4-methyinaphthyl, 1 ,6-dimethylnaphthyl or 4-tert-butyinaphthyl.

C₁-C₄Alkyl-substituted cyclohexyl which preferably contains 1 to 3, morepreferably 1 or 2, branched or unbranched alkyl group radicals, is e.g.cyclopentyl, methyl cyclopentyl, dimethylcyclopentyl, cyclohexyl,methylcyclohexyl, dimethylcyclohexyl, trimethylcyclohexyl ortert-butylcyclohexyl.

A mono-, di-, tri- or tetra-valent metal cation is preferably an alkalimetal, alkaline earth metal, heavy metal or aluminium cation, forexample Na⁺, K⁺, Mg⁺⁺, Ca⁺⁺, Ba⁺⁺, Zn⁺⁺, Al⁺⁺⁺, or Ti⁺⁺⁺⁺. Ca⁺⁺ isparticularly preferred.

Preferred compounds of formula I are those containing at least onetert-butyl group as R₁ or R₂. Very particularly preferred compounds arethose, wherein R₁ and R₂ are at the same time tert-butyl.

n is preferably 1 or 2 and, in particular 1.

For example the phosphonate is of formula Ia

wherein

-   R₁₀₁ is H, isopropyl, tert-butyl, cyclohexyl, or cyclohexyl which is    substituted by 1-3 C₁-C₄alkyl groups,-   R₁₀₂ is hydrogen, C₁-C₄alkyl, cyclohexyl, or cyclohexyl which is    substituted by 1-3 C₁-C₄alkyl groups,-   R₁₀₃ is C₁-C₂₀alkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl    or naphthyl,-   R₁₀₄ is hydrogen, C₁-C₂₀alkyl, unsubstituted or    C₁-C₄alkyl-substituted phenyl or naphthyl; or-   M^(r+)/r;-   M^(r+) is an r-valent metal cation, r is 1, 2, 3 or 4; and-   n is 1, 2, 3, 4, 5 or 6.

Preferably the phosphonate is of formula III, IV, V, VI or VII

wherein the R₁₀₁ are each independently of one another hydrogen orM^(r+)/r;

In general preferred is a process wherein a compound of formula (I) ascomponent a1) is added.

Specific examples of compounds of formula (I) are of the formula P1 orP2

A specific example of a compound of formula (II) isbis(2,4,4-trimethylpentyl)phosphonic acid.

The fluorescent whitening agents of formulae (1)-(8) are in theirmajority items of commerce or can be prepared as for example describedin Fluorescent Whitening Agents, edited by R. Anliker and G. Müller,Georg Thieme, 1975. In particular those of formula (1) can be preparedunder known reaction conditions by reacting cyanuric chloride with thecorresponding aminostilbenesulfonic acids and an amino compound that iscapable of introducing a group R₁, and with a compound that is capableof introducing a group R₂, wherein R₁ and R₂ are as defined above.

The fluorescent whitening agents that can be used advantageously in thepresent invention are listed by way of example in the following Table 1:TABLE 1 Compound of formula  (9)

(10)

(11)

(12)

(13)

(14)

(15)

(16)

(17)

(18)

(19)

(20)

(21)

(22)

(23)

(24)

(25)

(26)

Preference is given to a process wherein the compounds of formulae 1-8are the compounds

In a specific embodiment of the invention the compounds of formula (I)or (II) are added in an amount from 0.01 to 5%, preferably 0.05 to 1% byweight, based on the weight of the polycondensate.

Particularly preferred are compounds F2 and F3.

For example, the compounds of formulae 1-8 are added in an amount of0.001 to 0.5%, preferably 0.005 to 0.2% by weight, based on the weightof the polycondensate.

For instance the weight ratio of the compounds according to formula (I)and/or (II) to the compounds of formulae 1-8 is from 50:1 to 1:1.

For example the melt processing is carried out in such a way that themaximum mass-temperature of the melt is from 170° to 320° C.

Processing the polycondensate in the melt means heating above themelting point or glass transition temperature usually carried out, withstirring, until the blend is homogeneous. The temperature depends inthis case on the polycondensate used, for example:

-   -   260 to 290° C. for fibre- and film-grade PET    -   270 to 310° C. for bottle- and industrial-yarn-grade PET    -   240 to 290° C. for PBT    -   170 to 240° C. for amorphous PET-grades    -   220 to 280° C. for thermoplastic elastomers based on polyesters    -   280 to 320° C. for PC    -   270 to 290° C. for PA 6.6    -   240 to 270° C. for PA 6

The appropriate processing temperature in dependence on type and gradeof polycondensates can be found in “Kunststoff Taschenbuch” 21^(th)edition, edited by H. Saechtling, Carl Hanser Verlag 1979.”

The incorporation can be carried out in any heatable container equippedwith a stirrer, e.g. in a closed apparatus such as a kneader, mixer orstirred vessel. The incorporation is preferably carried out in anextruder or in a kneader. It is immaterial whether processing takesplace in an inert atmosphere or in the presence of oxygen.

The addition of the additive or additive blend to the polycondensate canbe carried out In all customary mixing machines in which thepolycondensate is melted and mixed with the additives. Suitable machinesare known to those skilled in the art. They are predominantly mixers,kneaders and extruders.

The process is preferably carried out in an extruder by introducing theadditive during processing.

Particularly preferred processing machines are single-screw extruders,contrarotating and corotating twin-screw extruders, planetary-gearextruders, ring extruders or cokneaders. It is also possible to useprocessing machines provided with at least one gas removal compartmentto which a vacuum can be applied.

Suitable extruders and kneaders are described, for example, in Handbuchder Kunststoffextrusion, Vol. 1 Grundlagen, Editors F. Hensen, W Knappe,H. Potente, 1989, pp. 3-7, ISBN:3-446-14339-4 (Vol. 2 Extrusionsanlagen1986, ISBN 3-446-14329-7).

For example, the screw length is 1-60 screw diameters, preferably 35-48screw diameters. The rotational speed of the screw is preferably 10-600rotations per minute (rpm), very particularly preferably 25-300 rpm.

If a plurality of components are added, these can be premixed or addedindividually.

The additives of the invention and optional further additives orcatalysts can be added during any step of the synthesis of thepolycondensate, e.g. within initial preparation of the monomer mixture,during formation of oligomers or during melt polycondensation. Theadditives can be added either as such, or dissolved or dispersed in aliquid or solid medium. The liquid or solid medium can be, for example,monomers or catalysts. The addition can be performed at ambienttemperature and pressure, or at temperatures and pressures adjusted tothe needs of the production process. In batch processes the additivesare advantageously added batch wise, in continuous production processes,the additives can be added in portions of batches or continuously.

The additives of the invention and optional further additives can alsobe added to the polycondensate in the form of a masterbatch(“concentrate”) which contains the components in a concentration of, forexample, about 1% to about 40% and preferably 2% to about 20% by weightincorporated in a polycondensate. The polycondensate must not benecessarily of identical structure than the polycondensate where theadditives are added finally. In such operations, the polycondensate canbe used in the form of powder, granules, solutions, suspensions or inthe form of latices.

Incorporation can take place prior to or during the shaping operation,or by applying the dissolved or dispersed compound to thepolycondensate, with or without subsequent evaporation of the solvent.

The processing apparatus is preferably a single-screw extruder,twin-screw extruder, planetary-gear extruder, ring extruder orKo-kneader having optionally one vent zone to which low pressure isapplied.

A preferred process is that, which comprises applying an underpressureof less than 250 mbar, particularly preferably of less than 100 mbarand, very particularly preferably, of less than 50 mbar, to the ventzone.

Another preferred process is that, wherein the processing apparatus is aclosely intermeshing twin-screw extruder or ring extruder with screwsrotating in the same direction and with a feed section, a transitionsection, at least one vent zone and a metering zone, the vent zone beingseparated from the transition section or from another vent zone by afusible plug. This separation via a fusible plug can be effected, forexample, by a combination of a kneading element and a return screwelement.

The processing apparatus preferably has 1-4 vent zones, particularlypreferably 1-3.

The process is usually carried out under normal pressure. Typicalprocessing times are from 10 seconds to 10 minutes.

Another aspect of the invention is a polycondensate obtainable in aprocess as described above.

Further aspects are a composition comprising a polycondensate and

-   a1) a compound of formula (I); or-   a2) a compound of formula (II); or-   a3) a compound of formula (I) and (II) and-   b) a compound of formulae 1-8 as described in the process above; and    the use of a mixture of-   a1) a compound of formula (I); or-   a2) a compound of formula (II); or-   a3) a compound of formula (I) and (II) and-   b) a fluorescent whitening agent selected from the group consisting    of a compound according to formulae 1-8 or a mixture thereof    for improving color and brightness of a polycondensate during the    polycondensation reaction.

It is preferred, that no Al containing condensation catalyst is stillpresent or has been used for the production of the polycondensate.

The definitions and preferences given above for the process apply alsofor the other aspects of the invention.

Further additives may be present in the polycondensate in addition tothe above mentioned novel additive blend. Examples thereof are listedbelow.

1. Antioxidants

1.1. Alkylated monophenols, for example2,6-di-tert-butyl-4-methylphenol, 24ert-butyl-4,6-di-methylphenol,2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl4-nbutylphenol,2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol,2-(α-methylcyclohexyl)-4,6-dimethyl-phenol,2,6-dioctadecyl4-methylphenol, 2,4,6-tricyclohexylphenol,2,6-di-tert-butyl-methoxymethylphenol, nonylphenols which are linear orbranched in the side chains, for example 2,6-di-nonyl-4-methylphenol,2,4-dimethyl-(1′-methylundec-1′-yl)phenol,2,4-dimethyl-6-(1′-methylheptadec-1′-yl)phenol,2,4-dimethyl-6-(1′-methyltridec-1′-yl)phenol and mixtures thereof.

1.2. Alkylthiomethylphenols, for example2,4-dioctylthiomethyl-6-tert-butylphenol,2,4-dioctyl-thiomethyl-6-methylphenol,2,4-dioctylthiomethyl-6-ethylphenol,2,6-di-dodecylthiomethyl-4-nonylphenol.

1.3. Hydroquinones and alkylated hvdroquinones, for example2,6-di-tert-butyl-4-methoxy-phenol, 2,5-di-tert-butylhydroquinone,2,5-di-tert-amylhydroquinone, 2,6-diphenyl-4-octade-cyloxyphenol,2,6-di-tert-butylhydroquinone, 2,5-di-tert-butyl-4-hydroxyanisole,3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenylstearate, bis-(3,5-di-tert-butyl4-hydroxyphenyl) adipate.

1.4. Tocopherols, for example α-tocopherol, β-tocopherol, γ-tocopherol,δ-tocopherol and mixtures thereof (Vitamin E).

1.5. Hydroxylated thiodiphenyl ethers, for example2,2′-thiobis(6-tert-butyl-4-methylphenol), 2,2′-thiobis(4-octylphenol),4,4′-thiobis(6-tert-butyl-3-methylphenol),4,4′-thiobis(6-tert-butyl-2-methylphenol),4,4′-thiobis-(3,6-di-sec-amylphenol),4,4′-bis(2,6-dimethyl-4-hydroxyphenyl)disulfide.

1.6. Alkylidenebisphenols, for example2,2′-methylenebis(6-tert-butyl-4-methylphenol),2,2′-methylenebis(6-tert-butyl-4-ethylphenol),2,2′-methylenebis[4-methyl-6-(α-methylcyclohexyl)-phenol],2,2′-methylenebis(4-methyl-6-cyclohexylphenol),2,2′-methylenebis(6-nonyl-4-methylphenol),2,2′-methylenebis(4,6-di-tert-butylphenol),2,2′-ethylidenebis(4,6-di-tert-butylphenol),2,2′-ethylidenebis(6-tert-butyl-4-isobutylphenol),2,2′-methylenebis[6-(α-methylbenzyl)-4-nonylphenol],2,2′-methylenebis[6-(α,α-dimethylbenzyl)-4-nonylphenol],4,4′-methylenebis-(2,6-di-tert-butylphenol),4,4′-methylenebis(6-tert-butyl-2-methylphenol),1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)butane,2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methyl-phenol,1,1,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane,1,1-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-3-n-dodecylmercaptobutane,ethylene glycol bis[3,3-bis(3′-tert-butyl-4′-hydroxyphenyl)butyrate],bis(3-tert-butyl-4-hydroxy-5-methyl-phenyl)dicyclopentadiene,bis[2-(3′-tert-butyl-2′-hydroxy-5′-methylbenzyl)-6-tert-butyl4-methylphenyl]terephthalate,1,1-bis-(3,5-dimethyl-2-hydroxyphenyl)butane,2,2-bis-(3,5-di-tert-butyl-4-hydroxyphenyl)propane,2,2-bis(5-tert-butyl-4-hydroxy-2-methylphenyl)-4-n-dodecylmercaptobutane,1,1,5,5-tetra-(5-tert-butyl-4-hydroxy-2-methylphenyl)pentane.

1.7. O-, N- and S-benzyl compounds, for example3,5,3′,5′-tetra-tert-butyl-4,4′-dihydroxydibenzyl ether,octadecyl-4-hydroxy-3,5-dimethylbenzylmercaptoacetate,tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate,tris(3,5-di-tert-butyl-4-hydroxybenzyl)amine,bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephthalate,bis(3,5-di-tert-butyl-4-hydroxy-benzyl)sulfide,isooctyl-3,5-di-tert-butyl-4-hydroxybenzylmercaptoacetate.

1.8. Hydroxybenzylated malonates, for exampledioctadecyl-2,2-bis(3,5-di-tert-butyl-2-hydroxybenzyl)malonate,di-octadecyl-2-(3-tert-butyl-4-hydroxy-5-methylbenzyl)malonate,dido-decylmercaptoethyl-2,2-bis-(3,5-di-tert-butyl-4-hydroxybenzyl)malonate,bis[4-(1,1,3,3-tetra-methylbutyl)phenyl]-2,2-bis(3,5-di-tert-butyl-4-hydroxybenzyl)malonate.

1.9. Aromatic hydroxybenzyl compounds, for example1,3,5-tris(3,5-di-tert-butyl-4-hydroxy-benzyl)-2,4,6-trimethylbenzene,1,4-bis(3,5-di-tert-butyl-4hydroxybenzyl)-2,3,5,6-tetrame-thylbenzene,2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol.

1.10. Triazine compounds, for example2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4-hydroxy-anilino)-1,3,5-triazine,2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine,2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,3,5-triazine,2,4,6-tris-(3,5-di-tert-butyl-4-hydroxyphenoxy)-1,2,3-triazine,1,3,5-tris-(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate,1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanurate,2,4,6-tris-(3,5-di-tert-butyl-4-hydroxyphenylethyl)-1,3,5-triazine,1,3,5-tris(3,5-di-tert-butyl4-hydroxy-phenylpropionyl)hexahydro-1,3,5-triazine,1,3,5-tris(3,5-dicyclohexyl-4-hydroxybenzyl)isocyanurate.

1.11. Acylaminophenols, for example 4-hydroxylauranilide,4-hydroxystearanilide, octylN-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate.

1.12. Esters of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid withmono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol,i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethyleneglycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide, 3-thiaundecanol,3-thiapentadecanol, trimethylhexanediol, trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.13. Esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acidwith mono- or polyhydric alcohols, e.g. with methanol, ethanol,n-octanol, i-octanol, octadecanol, 1,6-hexanediol, 1,9-nonanediol,ethylene glycol, 1,2-propanediol, neopentyl glycol, thiodiethyleneglycol, diethylene glycol, triethylene glycol, pentaerythritol,tris(hydroxyethyl) isocyanurate, N,N′-bis-(hydroxyethyl)oxamide,3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.14. Esters of β-(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid withmono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol,octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethyleneglycol, triethylene glycol, pentaerythritol,tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide,3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.15. Esters of 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid with mono-or polyhydric alcohols, e.g. with methanol, ethanol, octanol,octadecanol, 1,6-hexanediol, 1,9-nonanediol, ethylene glycol,1,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethyleneglycol, triethylene glycol, pentaerythritol,tris(hydroxyethyl)isocyanurate, N,N′-bis(hydroxyethyl)oxamide,3-thiaundecanol, 3-thiapentadecanol, trimethylhexanediol,trimethylolpropane,4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1.16. Amides of β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid e.g.N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamide,N,N′-bis(3,5-di-tert-butyl-4-hydroxy-phenylproplonyl)trimethylenediamide,N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)-hydrazide,N,N′-bis[2-(3-[3,5-di-tert-butyl-4-hydroxyphenyl]propionyloxy)ethyl]oxamide(Naugard®XL-1 supplied by Uniroyal).

1.17. Ascorbic acid (vitamin C)

1.18. Aminic antioxidants, for exampleN,N′-di-isopropyl-p-phenylenediamine,N,N′-di-sec-butyl-p-phenylenediamine,N,N′-bis(1,4-dimethylpentyl)-p-phenylenediamine,N,N′-bis(1-ethyl-3-methylpentyl)-p-phenylenediamine,N,N′-bis(1-methylheptyl)-p-phenylenediamine,N,N′-dicyclohexyl-p-phenylenediamine, N,N′-diphenyl-p-phenylenediamine,N,N′-bis(2-naphthyl)-p-phenylenediamine,N-isopropyl-N′-phenyl-p-phenylenediamine,N-(1,3-dimethylbutyl)-N′-phenyl-p-phenylenediamine,N-(1-methylheptyl)-N′-phenyl-p-phenylenediamine,N-cyclohexyl-N′-phenyl-p-phenlenediamine,4-(p-toluenesulfamoyl)diphenylamine,N,N′-dimethyl-N,N′-di-sec-butyl-p-phenylenediamine, diphenylamine,N-allyldiphenylamine, 4-isopropoxydiphenylamine,N-phenyl-1-naphthylamine, N-(4-tert-octylphenyl)-1-naphthylamine,N-phenyl-2-naphthylamine, octylated diphenylamine, for examplep,p′-di-tert-octyidiphenylamine, 4-nbutylaminophenol,4-butyrylaminophenol, 4-nonanoylaminophenol, 4-dodecanoylaminophenol,4-octadecanoylaminophenol, bis(4-methoxyphenyl)amine,2,6-di-tert-butyl-4-dimethylaminomethylphenol,2,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane,N,N,N′,N′-tetramethyl-4,4′-diaminodiphenylmethane,1,2-bis[(2-methylphenyl)amino]ethane, 1,2-bis(phenylamino)propane,(o-tolyl)biguanide, bis[4-(1′,3′-dimethylbutyl)phenyl]amine,tert-octylated N-phenyl-1-naphthylamine, a mixture of mono- anddialkylated tert-butyl/tert-octyldiphenylamines, a mixture of mono- anddialkylated nonyldiphenylamines, a mixture of mono- and dialkylateddodecyidiphenylamines, a mixture of mono- and dialkylatedisopropyllisohexyldiphenylamines, a mixture of mono- und dialkylatedtert-butyidiphenylamines, 2,3-dlhydro-3,3-dimethyl-4H-1,4-benzothiazine,phenothiazine, a mixture of mono- und dialkylatedtert-butyl/tert-octylphenothiazines, a mixture of mono- und dialkylatedtert-octyl-phenothiazines, N-allylphenothiazin,N,N,N′,N′-tetraphenyl-1,4-diaminobut-2-ene,N,N-bis(2,2,6,6-tetramethyl-piperid-4-yl-hexamethylenediamine,bis(2,2,6,6-tetramethylpiperid-4-yl)sebacate,2,2,6,6-tetramethylpiperidin-4-one, 2,2,6,6-tetramethylpiperidin-4-ol.

2. UV absorbers and light stabilisers

2.1. 2-(2′-Hydroxyphenyl)benzotriazoles, for example2-(2′-hydroxy-5′-methylphenyl)benzotriazole,2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)benzotriazole,2-(5′-tert-butyl-2′-hydroxyphenyl)benzotriazole,2-(2′-hydroxy-5′-(1,1,3,3-tetramethylbutyl)phenyl)benzotriazole,2-(3′,5′-di-tert-butyl-2′-hydroxyphenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-methylphenyl)-5-chloro-benzotriazole,2-(3′-sec-butyl-5′-tert-butyl-2′-hydroxyphenyl)benzotriazole,2-(2′-hydroxy-4′-octyloxyphenyl)benzotriazole,2-(3′,5′-di-tert-amyl-2′-hydroxyphenyl)benzotriazole,2-(3′,5′-bis-(α,α-dimethylbenzyl)-2′-hydroxyphenyl)benzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonylethyl)phenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxyphenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)-5-chlorobenzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-methoxycarbonylethyl)phenyl)benzotriazole,2-3′-tert-butyl-2′-hydroxy-5′-(2-octyloxycarbonyl-ethyl)phenyl)benzotriazole,2-(3′-tert-butyl-5′-[2-(2-ethylhexyloxy)carbonylethyl]-2′-hydroxy-phenyl)benzotriazole,2-(3′-dodecyl-2′-hydroxy-5′-methylphenyl)benzotriazole,2-(3′-tert-butyl-2′-hydroxy-5′-(2-isooctyloxycarbonylethyl)phenylbenzotriazole,2,2′-methylenebis[4-(1,1,3,3-tetramethylbutyl)-6-benzotriazole-2-ylphenol];the transesterification product of2-[3′-tert-butyl-5′-(2-methoxycarbonylethyl)-2′-hydroxyphenyl]-2H-benzotriazolewith polyethylene glycol 300; [R—CH₂—CH₂—COO—CH₂CH₂—]₂ whereR=3′-tert-butyl-4′-hydroxy-5′-2H-benzotriazol-2-ylphenyl,2-[2′-hydroxy-3′-(α,α-dimethylbenzyl)-5′-(1,1,3,3-tetramethylbutyl)phenyl]-benzotriazole;2-[2′-hydroxy-3′-(1,1,3,3-tetramethylbutyl)-5′-(α,α-dimethylbenzyl)phenyl]benzotriazole.

2.2. 2-Hydroxybenzophenones, for example the 4-hydroxy, 4-methoxy,4-octyloxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2′,4′-trihydroxyand 2′-hydroxy-4,4′-dimethoxy derivatives.

2.3. Esters of substituted and unsubstituted benzoic acids, as forexample 4-tertbutyl-phenyl salicylate, phenyl salicylate, octylphenylsalicylate, dibenzoyl resorcinol, bis(4-tert-butylbenzoyl)resorcinol,benzoyl resorcinol, 2,4-di-tert-butylphenyl3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl3,5-di-tertbutyl-4-hydroxybenzoate, octadecyl3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl3,5-di-tert-butyl-4-hydroxybenzoate.

2.4. Acrylates, for example ethyl α-cyano-β,β-diphenylacrylate, isooctylα-cyano-β,β-diphenylacrylate, methyl α-carbomethoxycinnamate, methylα-cyano-β-methyl-p-methoxycinnamate, butylα-cyano-β-methyl-p-methoxycinnamate, methylα-carbomethoxy-p-methoxycinnamate andN-(β-carbomethoxy-β-cyanovinyl)-2-methylindoline.

2.5. Nickel compounds, for example nickel complexes of2,2′-thio-bis-[4-(1,1,3,3-tetramethyl-butyl)phenol], such as the 1:1 or1:2 complex, with or without additional ligands such as n-butylamine,triethanolamine or N-cyclohexyldiethanolamine, nickeldibutyldithiocarbamate, nickel salts of the monoalkyl esters, e.g. themethyl or ethyl ester, of 4-hydroxy-3,5-di-tert-butylbenzylphosphonicacid, nickel complexes of ketoximes, e.g. of 2-hydroxy-4-methylphenylundecylketoxime, nickel complexes of1-phenyl-4-lauroyl-5-hydroxypyrazole, with or without additionalligands.

2.6. Sterically hindered amines, for examplebis(2,2,6,6-tetramethyl-4-piperidyl)sebacate,bis(2,2,6,6-tetramethyl-4-piperidyl)succinate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate,bis(1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl)sebacate,bis(1,2,2,6,6-pentamethyl-4-piperidyl)n-butyl-3,5di-tert-butyl-4-hydroxybenzylmalonate,the condensate of1-(2-hydroxyethyl)-2,2,6,6-tetramethyl-4-hydroxypiperidine and succinicacid, linear or cyclic condensates ofN,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and4-tert-octylamino-2,6-di-chloro-1,3,5-triazine,tris(2,2,6,6-tetramethyl-4-piperidyl)nitrilotriacetate,tetrakis(2,2,6,6-tetra-methyl-4-piperidyl)-1,2,3,4-butanetetracarboxylate,1,1′-(1,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone),4-benzoyl-2,2,6,6-tetramethylpiperidine,4-stearyloxy-2,2,6,6-tetramethyl-piperidine,bis(1,2,2,6,6-pentamethylpiperidyl)-2-n-butyl-2-(2-hydroxy3,5-di-tert-butylbenzyl)-malonate,3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione,bis(1-octyl-oxy-2,2,6,6-tetramethylpiperidyl)sebacate,bis(1-octyloxy-2,2,6,6-tetramethylpiperidyl)succinate, linear or cycliccondensates ofN,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylene-diamine and4-morpholino-2,6-dichloro-1,3,5-triazine, the condensate of2-chloro-4,6-bis(4-n-butylamino-2,2,6,6-tetramethylpiperidyl)-1,3,5-triazineand 1,2-bis(3-aminopropylamino)-ethane, the condensate of2-chloro-4,6-di-(4-n-butylamino-1,2,2,6,6-pentamethylpiperidyl)1,3,5-triazine and 1,2-bis-(3-aminopropylamino)ethane,8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]decane-2,4-dione,3-dodecyl-1-(2,2,6,6-tetramethyl-4-piperidyl)pyrrolidin-2,5-dione,3-dodecyl-1-(1,2,2,6,6-pentamethyl-4-piperidyl)pyrrolidine-2,5-dione, amixture of 4-hexadecyloxy- and4-stearyloxy-2,2,6,6-tetramethylpiperidine, a condensation product ofN,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine and4-cyclohexylamino-2,6-dichloro-1,3,5-triazine, a condensation product of1,2-bis(3-aminopropylamino)ethane and 2,4,6-trichloro-1,3,5-triazine aswell as 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No.[136504-96-6]); N-(2,2,6,6-tetramethyl-4-piperidyl)-n-dodecylsuccinimid,N-(1,2,2,6,6-pentamethyl-4-piperidyl)-n-dodecylsuccinimid,2-undecyl-7,7,9,9-tetramethyl-1-oxa-3,8-diaza-4-oxo-spiro[4,5]decane, areaction product of7,7,9,9-tetramethyl-2-cycloundecyl-1-oxa-3,8-diaza-4-oxospiro[4,5]decane und epichlorohydrin,1,1-bis(1,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl)-2-(4-methoxyphenyl)ethene,N,N′-bis-formyl-N,N′-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamine,diester of 4-methoxy-methylenemalonic acid with1,2,2,6,6-pentamethyl-4-hydroxypiperidine,poly[methylpropyl-3-oxy-4-(2,2,6,6-tetramethyl-4-piperidyl)]siloxane,reaction product of maleic acid anhydride-α-olefin-copolymer with2,2,6,6-tetramethyl-4-aminopiperidine or1,2,2,6,6-pentamethyl-4-aminopiperidine.

2.7. Oxamides, for example 4,4′-dioctyloxyoxanilide,2,2′-diethoxyoxanilide, 2,2′-dioctyloxy-5,5′-di-tert-butoxanilide,2,2′-didodecyloxy-5,5′-di-tert-butoxanilide, 2-ethoxy-2′-ethyloxanilide,N,N′-bis(3-dimethylaminopropyl)oxamide,2-ethoxy-5-tert-butyl-2′-ethoxanilide and its mixture with2-ethoxy-2′-ethyl-5,4′-di-tert-butoxanilide, mixtures of o- andp-methoxy-disubstituted oxanilides and mixtures of o- andp-ethoxy-disubstituted oxanilides.

2.8. 2-(2-Hydroxyphenyl)-1,3,5-triazines, for example2,4,6-tris(2-hydroxy4-octyloxyphenyl)-1,3,5-triazine,2-2-hydroxy4-octyloxyphenyl)4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2,4-bis(2-hydroxy4-propyl-oxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-octyloxyphenyl)-4,6-bis(4-methylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-dodecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-[2-hydroxy-4-(2-hydroxy-3-butyloxy-propoxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine,2-[2-hydroxy-4-(2-hydroxy-3-octyloxy-propyloxy)phenyl]-4,6-bis(2,4-dimethyl)-1,3,5-triazine,2-[4-(dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxy-phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-[2-hydroxy-4-(2-hydroxy-3-dodecyloxypropoxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-(2-hydroxy-4-hexyloxy)phenyl-4,6-diphenyl-1,3,5-triazine,2-2-hydroxy-4-methoxyphenyl)-4,6-diphenyl-1,3,5-triazine,2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]-1,3,5-triazine,2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1,3,5-triazine,2-{2-hydroxy-4-[3-(2-ethylhexyl-1-oxy)-2-hydroxypropyloxy]phenyl}-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine.

3. Metal deactivators, for example N,N′-diphenyloxamide,N-salicylal-N′-salicyloyl hydrazine, N,N′-bis(salicyloyl) hydrazine,N,N′-bis(3,5-di-tert-butyl-4-hydroxyphenylpropionyl) hydrazine,3-salicyloylamino-1,2,4-triazole, bis(benzylidene)oxalyl dihydrazide,oxanilide, isophthaloyl dihydrazide, sebacoyl bisphenylhydrazide,N,N′-diacetyladipoyl dihydrazide, N,N′-bis(salicyloyl)oxalyldihydrazide, N,N′-bis(salicyloyl)thiopropionyl dihydrazide.

4. Hydroxylamines, for example, N,N-dibenzylhydroxylamine,N,N-diethylhydroxylamine, N,N-dioctylhydroxylamine,N,N-dilaurylhydroxylamine, N,N-ditetradecylhydroxylamine,N,N-dihexadecylhydroxylamine, N,N-dioctadecylhydroxylamine,N-hexadecyl-N-octadecylhydroxylamine,N-heptadecyl-N-octadecylhydroxylamine, N,N-dialkylhydroxylamine derivedfrom hydrogenated tallow amine.

5. Nitrones, for example, N-benzyl-alpha-phenyinitrone,N-ethyl-alpha-methyinitrone, N-octyl-alpha-heptylnitrone,N-lauryl-alpha-undecylnitrone, N-tetradecyl-alpha-tridcylnitrone,N-hexa-decyl-alpha-pentadecylnitrone,N-octadecyl-alpha-heptadecyinitrone,N-hexadecyl-alpha-heptadecyinitrone,N-ocatadecyl-alpha-pentadecylnitrone,N-heptadecyl-alpha-heptadecyl-nitrone,N-octadecyl-alpha-hexadecylnitrone, nitrone derived fromN,N-dialkylhydroxylamine derived from hydrogenated tallow amine.

6. Thiosynergists, for example dilauryl thiodipropionate or distearylthiodipropionate.

7. Peroxide scavengers, for example esters of β-thiodipropionic acid,for example the lauryl, stearyl, myristyl or tridecyl esters,mercaptobenzimidazole or the zinc salt of 2-mercaptobenzimidazole, zincdibutyidithiocarbamate, dioctadecyl disulfide, pentaerythritoltetrakis(β-dodecylmercapto)propionate.

8. Polyamide stabilisers, for example copper salts in combination withiodides and/or phosphorus compounds and salts of divalent manganese.

9. Basic co-stabilisers, for example, melamine, polyvinylpyrrolidone,dicyandiamide, triallyl cyanurate, urea derivatives, hydrazinederivatives, amines, polyamides, polyurethanes, alkali metal salts andalkaline earth metal salts of higher fatty acids, for example calciumstearate, zinc stearate, magnesium behenate, magnesium stearate, sodiumricinoleate and potassium palmitate, antimony pyrocatecholate or zinkpyrocatecholate.

10. Nucleating agents, for example, Inorganic substances such as talcum,metal oxides such as titanium dioxide or magnesium oxide, phosphates,carbonates or sulfates of, preferably, alkaline earth metals; organiccompounds such as mono- or polycarboxylic acids and the salts thereof,e.g. 4-tert-butylbenzoic acid, adipic acid, diphenylacetic acid, sodiumsuccinate or sodium benzoate; polymeric compounds such as ioniccopolymers (ionomers).

11. Fillers and reinforcing agents, for example calcium carbonate,silicates, glass fibres, glass bulbs, asbestos, talc, kaolin, mica,barium sulfate, metal oxides and hydroxides, carbon black, graphite,wood flour and flours or fibers of other natural products, syntheticfibers.

12. Other additives, for example, plasticisers, lubricants, emulsifiers,pigments, rheology additives, catalysts, flow control agents, opticalbrighteners, flameproofing agents, antistatic agents and blowing agents.

Phenolic antioxidants and UV-absorber are preferred.

The following examples illustrate the invention.

Analytical Procedures:

Intrinsic Viscosity (I.V.):

According to DIN 53728-3, Edition 1985-01: 1 g polymer is dissolved in100 g of a mixture of phenol/di-chloro-benzene (1/1). The viscosity ofthis solution is measured at 30° C. in an Ubelode-viscosimeter andrecalculated to the intrinsic viscosity.

Color:

Color (b, L value of the Yellowness Index) was measured according toASTM D1925. Following Instrument was used: Hunter Lab Scan.

Materials:

-   Terephthalic acid-   Isophthalic acid-   Ethylene glycol

Antimony trioxide as catalyst.

IRGAMOD® 195: a compound according to formula (I), which is a commercialproduct of Ciba Specialty Chemicals.

Uvitex® OB-One (compound F3)

PET Synthesis:

General Polymerization Procedure

1,621.3 g ethylene glycol, 3,338.5 g terephthalic acid, 66.8 gisophthalic acid and 1.3575 g antimony trioxide are mixed within a metalcontainer. The mixture is transferred into a 10 l reactor (stainlesssteel) fitted with stirrer, refluxing unit and an outlet-die at thebottom of the reactor. The reactor can be either pressurized withnitrogen up to 6 bars or operated under vacuum down to 1 mbar. Themonomer mixture is heated from room temperature to 250° C. within 30mins. During heating phase pressure is increased up to 4 bar. Awater/ethylene glycol mixture is distilled off for 3.5 h. Temperature isincreased consecutively to 280° C. Within the next 5 h pressure iscontinuously reduced to further distill off water and ethylene glycol.The polyester product is extruded through the bottom die, cooled to roomtemperature in a water bath and pelletized to yield clear PET granules.

Typically, by this procedure a PET is synthesized with followingproperties:

-   I.V.: 0.75 dl/g;-   Color: b=4, L=75

COMPARATIVE EXAMPLES A AND B

The general procedure described above is repeated with the onlydifference that compounds listed in the following table were added.Comp. Ex. No. Additive A 500 ppm Irgamod 195 B 100 ppm Uvitex OB-One

The resulting PET shows both better color than PET without Irgamod 195or Uvitex OB-One.

Inventive Example 1

The general procedure described above is repeated with the onlydifference that the compounds listed in the following table were added.Example No. Additive 1 400 ppm Irgamod 195 +  80 ppm Uvitex OB-One

The resulting PET, shows significantly less color than the PET resultingfrom the comparative examples A and B.

The prepared PETs were subjected to an SSP (10 h, 220° C. within vacuumtumbling dryer) and injection molded into plaques. Color (b* value ofthe color difference formula) is measured according to ASTM D1925 usinga Hunter Lab Scan spectrometer. Additives YI L* B* Comp. Without 5.7 754.0 Comp. A 500 ppm IRGAMOD 195 3.9 79 2.9 Comp. B 100 ppm UVITEX-OB-One2.6 83 3.5 Ex 1 400 ppm IRGAMOD 195 0.72 86 0.5  80 ppm UVITEX-OB-OneExample 1 shows the best color values in both L*-value and b*-value.

1. A process for the preparation of a polycondensate in a condensation reaction of monomers or oligomers or the modification of a polycondensate by melt processing or solid-state polycondensation of the polycondensate, comprising adding during the polycondensation reaction a1) a compound of formula (I)

wherein R₁₀₃ is H, C₁-C₂₀alkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl or naphthyl, R₁₀₄ is hydrogen, C₁-C₂₀alkyl, unsubstituted or C₁-C₄alkyl-substituted phenyl or naphthyl; or M^(r+)/r, M^(r+) is an r-valent metal cation or the ammonium ion, n is 0, 1, 2, 3, 4, 5 or 6, and r is 1, 2, 3 or 4; Q is hydrogen, —X—C(O)—OR₁₀₇, or a radical

R₁₀₁ is isopropyl, tert-butyl, cyclohexyl, or cyclohexyl which is substituted by 1-3 C₁-C₄alkyl groups, R₁₀₂ is hydrogen, C₁-C₄alkyl, cyclohexyl, or cyclohexyl which is substituted by 1-3 C₁-C₄alkyl groups, R₁₀₅ is H, C₁-C₁₈alkyl, OH, halogen or C₃-C₇cycloalkyl; R₁₀₆ is H, methyl, trimethylsilyl, benzyl, phenyl, sulfonyl or C₁-C₁₈alkyl; R₁₀₇ is H, C₁-C₁₀alkyl or C₃-C₇cycloalkyl; and X is phenylene, C₁-C₄alkyl group-substituted phenylene or cyclohexylene; or a2) a compound of formula (II)

wherein R₂₀₁ is hydrogen, C₁-C₂₀alkyl, phenyl or C₁-C₄alkyl substituted phenyl; biphenyl, naphthyl, —CH₂—O—C₁-C₂₀alkyl or —CH₂—S—C₁-C₂₀alkyl, R₂₀₂ is C₁-C₂₀alkyl, phenyl or C₁-C₄alkyl substituted phenyl; biphenyl, naphthyl, —CH₂—O—C₁-C₂₀alkyl or —CH₂—S—C₁-C₂₀alkyl, or R₁ and R₂ together are a radical of the formula III

wherein R₂₀₃, R₂₀₄ and R₂₀₅ independently of each other are C₁-C₂₀alkyl, phenyl or C₁-C₄alkyl substituted phenyl; R₂₀₆ is hydrogen, C₁-C₁₈alkyl or the ion of an alkali metal or the ammonium ion or R₂₀₆ is a direct bond, which forms together with R₂₀₂ an aliphatic or aromatic cyclic ester; or a3) a compound of formula (I) and formula (II); and b) a fluorescent whitening agent selected from the group consisting of compounds of formulae 1-8 and mixtures thereof

in which formulae

R₃ is an unsubstituted or substituted alkyl or aryl group; R₄ is M, or an unsubstituted or substituted alkyl or aryl group; R₅ is hydrogen; an unsubstituted or substituted alkyl or aryl group; or —NR₇R₈, wherein R₇ and R₈ are each independently of the other hydrogen or an unsubstituted or substituted alkyl or aryl group, or R₇ and R₈ together with the nitrogen atom linking them form a heterocyclic radical; R₆ is hydrogen, or an unsubstituted or substituted alkyl or aryl group; R₂ is hydrogen; an unsubstituted or substituted alkyl or aryl group; or a radical of formula

—N(CH₂CH₂OH)₂, —N[CH₂CH(OH)CH₃]₂, —NH—R₄, —N(R₄)₂ or —OR₄; or R₁ and R₂ are each independently of the other —OH, —Cl, —NH₂, —O—C₁-C₄alkyl, —O-aryl, —NH—C₁-C₄alkyl, —N(C₁-C₄alkyl)₂, —N(C₁-C₄alkyl)(C₁-C₄hydroxyalkyl), —N(C₁-C₄hydroxyalkyl)₂, —NH-aryl, morpholino or —S—C₁-C₄alkyl(aryl); R₉ and R₁₀ are each independently of the other hydrogen, C₁-C₄alkyl, phenyl or a radical of formula

R₁₁ is hydrogen, —Cl or SO₃M; R₁₂ is —CN, —SO₃M, —S(C₁-C₄alkyl)₂ or —S(aryl)₂; R₁₃ is hydrogen, —SO₃M, —O—C₁-C₄alkyl, —CN, —Cl, —COO—C₁-C₄alkyl or —CON(C₁-C₄alkyl)₂; R₁₄ is hydrogen, —C₁-C₄alkyl, —Cl or —SO₃M; R₁₅ and R₁₆ are each independently of the other hydrogen, C₁-C₄alkyl, —SO₃M, —Cl or —O—C₁-C₄alkyl; R₁₇ is hydrogen or C₁-C₄alkyl; R₁₈ is hydrogen, C₁-C₄alkyl, —CN, —Cl, —COO—C₁-C₄alkyl, —CON(C₁-C₄alkyl)₂, aryl or —O-aryl; M is hydrogen, sodium, potassium, calcium, magnesium, ammonium, mono-, di-, tri- or tetra-C₁-C₄alkylammonium, mono-, di- or tri-C₁-C₄hydroxyalkylammonium, or ammonium di- or tri-substituted by a mixture of C₁-C₄alkyl and C₁-C₄hydroxyalkyl groups; and n₁, n₂ and n₃ are each independently of the others 0 or
 1. 2. A process according to claim 1, wherein the polycondensate is polyethylene therephthalate (PET), polybutylene therephthalate (PBT), polyethylenenaphthenate (PEN), a copolyester, PA 6, PA 6, 6, or is a polycarbonate containing bisphenol A, bisphenol Z or bisphenol F linked via carbonate groups.
 3. A process according to claim 1, wherein the polycondensate is PBT, PET or a copolymer with PBT or PET.
 4. A process according to claim 1, wherein the polycondensate exhibits a L value, which is greater than 80 and a b value which is less than 2, as measured with a spectrometer according to ASTM D1925.
 5. A process according to claim 1, wherein a compound of formula (I) as component a1) is added.
 6. A process according to claim 5 wherein the compound of formula (I) is of the formula P1 or P2


7. A process according to claim 1 wherein the compounds of formulae 1-8 are the compounds


8. A process according to claim 1 wherein the compounds of formula (I) or (II) are added in an amount from 0.01 to 5% by weight, based on the weight of the polycondensate.
 9. A process according to claim 1 wherein the compounds of formulae 1-8 are added in an amount of 0.001 to 0.5% by weight, based on the weight of the polycondensate.
 10. A process according to claim 1 wherein the weight ratio of the compounds according to formula (I) and (II) to the compounds of formulae 1-8 is from 50:1 to 1:1.
 11. A process according to claim 1 wherein additionally a polyanhydride is added, which has 2-8 anhydride functions.
 12. A process according to claim 1 wherein a further polyfunctional compound is added, selected from the group consisting of a polyfunctional hydroxyl compound (polyol), a polyfunctional epoxy compound, a polyfunctional amine compound (polyamine), a polyfunctional aziridine compound (polyaziridine), a polyfunctional isocyanate compound (polyisocyanate), a polyfunctional oxazoline compound (polyoxazoline), a polyfunctional thioalcohol, and combinations thereof.
 13. A polycondensate obtained in a process according to claim
 1. 14. A composition comprising a polycondensate and a1) a compound of formula (I); or a2) a compound of formula (II); or a3) a compound of formula (I) and (II) and b) a compound of formulae 1-8 according to claim
 1. 15. (canceled) 